The present invention relates to peripheral storage devices and, more particularly, to a dual purpose serial/parallel data transfer device for use with a peripheral storage device.
Peripheral storage devices have become a standard feature in most computer systems. Such devices provide mass storage functionality for a host computer, and may include hard disk drives, CDROM drives, tape drives, and the like. For example, hard disk drives include one or more magnetically coated platters used for storing program instructions, data, and other information used by the computer system. One or more such platters may be configured in a stack, which may be rotated by a spindle or servo motor. A space is provided between each platter to allow an arm having a read/write head to be positioned on each side of each platter such that information may be stored and retrieved. Information may be stored on one or both sides of the platters, which are generally organized into sectors, tracks, zones, and cylinders.
The read/write heads may be mounted onto one or more suspension arms whereby each of the read/write heads may be positioned as desired. The suspension arms may be coupled together at a voice coil motor (VCM) to form one unit or assembly that is positionable by the voice coil motor. The voice coil motor positions the suspension arms so that an active read/write head is properly positioned for reading or writing information. The read/write heads may thus be positioned between an inner diameter and an outer diameter of the platters in a controlled fashion to access data stored thereon.
Hard disk drives and other peripheral storage devices also include a variety of electronic control circuitry for processing data and for controlling its overall operation, including a hard disk controller. For example, the controller may include a processor, a pre-amplifier, a read channel, a write channel, a servo controller, a motor control circuit, a read-only memory (ROM), a random-access memory (RAM), and a variety of disk control circuitry to control the operation of the hard disk drive and to properly interface the hard disk drive to a bus in a host computer system. The disk control circuitry generally includes a processor (e.g., a DSP, microprocessor, microcontroller, or the like) for executing instructions stored in memory to control the operation and interface of the hard disk drive.
The peripheral storage device performs write, read, and servo operations when storing and retrieving data. Generally, a write operation includes receiving data from a system bus and storing the data on the platters. In a read operation, the appropriate sector to be read is located and data that has been previously written to one or more platters is read. The data is then provided to the host computer system. The disk drive may further comprise some form of buffer memory to buffer or temporarily store information on its way from the host system to the storage media (platters) and/or on its way from the media to the host system. In addition, the control circuitry may include instruction memory (e.g., ROM, EEPROM, FLASH, and the like) used for storing firmware instructions for execution by the controller processor, and execution memory (e.g., SRAM) used for storing temporary variables, intermediate results, and the like (scratchpad).
Such peripheral storage devices are typically provided with a parallel data interface for interconnection with a host computer system. One popular form of parallel interface is known as the integrated drive electronics (IDE), sometimes also referred to as intelligent device electronics, and is widely used to connect hard disk drives, CDROM devices, tape drives, and the like to personal computers. This parallel interface employs a forty pin AT attachment (ATA) connector providing interconnection of sixteen bi-directional data lines and various handshaking or interface control signals between the disk drive system and the host computer. Separate cable connections may be provided therebetween in order to supply the disk drive system with power from the host computer.
While the parallel ATA/IDE interface has become a widely used standard in the computer disk drive industry, other forms of interconnection are being developed. For instance, high speed serial interfaces are being considered. However, where two or more interfaces are being used in the marketplace, it may be desirable to provide for universal interconnectivity between disk drives and/or host computers having one or both interfaces. Thus, there is a need for improved apparatus and methodologies for interfacing disk drive systems with host computers having support for multiple interface types.
The present invention provides a peripheral storage system and a data transfer device for use in such a system, which provide for selective information transfer between a disk drive or other peripheral storage device and a host computer in a serial or parallel data format. The invention further comprises a cable connector and cable assembly for connecting a dual function peripheral storage device with the host computer, whereby serial or parallel data transfer may be accomplished using differential or single-ended formats. The cable connector and cable assembly may be employed to connect with such devices using an ATA type connector on one or both of the peripheral storage device and the host computer, whereby a single cable having cable connectors on both ends may be employed to interconnect with devices including an ATA type connector as well as devices with other types of connectors. In addition, the invention provides a methodology for transferring data between a peripheral storage device and a host computer in one of a serial and a parallel data format as well as in one of a single-ended format and a differential format.
The invention thus provides for dual function (e.g., serial and parallel interface capable) peripheral storage device systems by the employment of a data transfer device in the peripheral storage device system. The data transfer device may also be employed in a host computer system to provide serial and parallel data transfer capability therein. The data transfer device may be adapted to interface serial and/or parallel data via a standard ATA type connector, or through a serial connector interface. The cable connector and cable assembly provide for connection to both such connector types, thus allowing a single cable assembly to be employed regardless of the connector types provided on the peripheral storage device and the host computer. In addition, the data transfer device may be adapted to operate in serial or parallel mode according to the type of cable used to interconnect the drive with the host computer. Consequently, the invention provides universal connectivity for peripheral storage device systems and host computers with serial or parallel interface capabilities.
One aspect of the invention provides a cable connector with a housing having an integer number N socket receptacles configured in a first pattern. Some of the receptacles include female sockets for interconnection with one or more signals in a male ATA or other type connector. The cable connector may be adapted to connect with the ATA connector in a single orientation, whereby proper interconnection of signals from the peripheral storage device to the host computer may be ensured. For example, a blocking device may be located in one of the socket receptacles to provide for proper interconnection with an ATA connector, which has an integer number M pins and a missing pin location, where N is less than M.
Thus, the connector, as well as cable assemblies including the connector, may be employed in interconnecting serial peripheral storage devices with serial host computers where one or both include an ATA connector. Additionally, the connector may be used to connect serial devices having connectors other than ATA types. For example, the peripheral storage device and/or the host computer may include a connector adapted for serial data transfer, which has fewer pins than the ATA connector. The connector thus facilitates cable assemblies universally applicable to devices (e.g., host computers and disk drives) having ATA or other (e.g., serial interface type) connectors. As an example, the cable connector may comprise two rows of three receptacles with one receptacle populated with a blocking device, whereby the connector may connect, in a single orientation, with an ATA type connector (e.g., on a disk drive or on a host computer) having 39 pins in a dual row pattern with a single missing pin location.
According to another aspect of the invention, the cable may provide for interconnection with four data signals of the ATA connector, through the proper placement of the blocking device. For example, a cable connector having a two row pattern with three receptacles in each row may be provided with a blocking device located in one of the corner receptacles, whereby interconnection with ATA connector positions used for data lines according to the ATA standard may be achieved.
When employed with a peripheral storage device using these connector positions for dual purpose (e.g., serial/parallel) data transfer, the peripheral storage device circuitry (e.g., such as a data transfer device according to another aspect of the invention) required to implement the dual functionality may be reduced or minimized as a result. For instance, providing serial or parallel data transfer using connector positions defined as data bits in the parallel ATA standard may be easier than providing such dual functionality with connector positions defined as non-data (e.g., handshaking) signals in the ATA standard. Thus, the employment of a blocking device minimizes or eliminates the possibility of improper connection with the peripheral storage device or host computer connector, while the location thereof in the cable connector advantageously provides for selective employment of data line connections in the multi-function data transfer circuitry.
In this regard, the invention also contemplates a cable assembly for interconnecting a peripheral storage device with a host computer which comprises a cable having a plurality of conductor wires extending between first and second ends, and at least one cable connector connected to the cable at one end thereof. The cable connector may be adapted to connect the cable to an ATA connector associated with the peripheral storage device or the host computer. In this regard, the cable connector may include N female sockets and is adapted to connect at least four data signals in the ATA connector to at least four of the conductor wires.
Another aspect of the invention provides a data transfer device for transferring information between the peripheral storage device and a host computer. The data transfer device may be employed in a peripheral storage device system in order to facilitate multi-function operation, such as serial/parallel data transfer modes. For example, the device may provide for bi-directional, single-ended parallel data transfer operation, or bi-directional, differential serial data transfer operation. The data transfer device comprises an output circuit operative to receive output information from the peripheral storage device and to selectively provide one of a single-ended output representative of the output information and a differential output representative of the output information to the host computer according to a control signal. In addition, the device includes an input circuit operative to selectively receive one of a single-ended input and a differential input from the host computer according to the control signal and to provide input information representative of the single-ended or differential input to the peripheral storage device.
The data transfer device may be advantageously employed in a peripheral storage device system having a single ATA type connector, to provide for both serial and parallel data transfer functionality. This allows peripheral storage device systems to be interfaced with host computers having one or the other (e.g., or both) of serial and parallel data transfer capabilities. The invention accordingly facilitates the provision of universally applicable peripheral storage device systems. In this regard, the multi-purpose cable connectors and cable assemblies of the invention may further facilitate such universal connectivity.
Yet another aspect of the invention provides a peripheral storage device system for providing information storage for a host computer, which may advantageously implement two or more modes of operation (e.g., serial and/or parallel data transfer modes). The drive system comprises a peripheral storage device operative to store information from the host computer, a host interface operative to provide electrical communication between the peripheral storage device and the host computer, and a data transfer device associated with the host interface and operative to selectively transfer information between the peripheral storage device and the host computer in one of a serial format and a parallel data format.
The data transfer device may comprise an output circuit operative to receive output information from the peripheral storage device and to selectively provide one of a single-ended output representative of the output information and a differential output representative of the output information to the host computer according to a control signal. In addition, the transfer device comprises an input circuit operative to selectively receive one of a single-ended input and a differential input from the host computer according to the control signal and to provide input information representative of the single-ended or differential input to the peripheral storage device.
According to still another aspect of the invention, a methodology is provided for transferring data between a peripheral storage device and a host computer in one of a serial format and a parallel format. The method comprises providing a data transfer device in the peripheral storage device, and selectively transferring information between the peripheral storage device and the host computer in one of a serial format and a parallel format according to a control signal using the data transfer device. The method may further comprise receiving output information from the peripheral storage device and selectively providing one of a single-ended output representative of the output information and a differential output representative of the output information to the host computer according to a first control signal using the data transfer device. In addition, the method may include selectively receiving one of a single-ended input and a differential :input from the host computer according to the first control signal and to providing input information representative of the single-ended or differential input to the peripheral storage device using the data transfer device.
The method may thus be utilized in transferring data between a peripheral storage device system and a host computer, which have one or both of serial and parallel data transfer modes of operation. In addition, the method provides for transfer of such data in either single-ended or differential modes.